Soot blower capable of maintaining efficiency of cooler

Abstract

The utility model discloses a soot blower for maintaining the efficiency of a cooler, which comprises a cooler for cooling hot gas containing solid particles and a steam pocket, and is characterized by also comprising a storage tank and a nitrogen source, the storage tank is filled with a purging medium, the bottom of the storage tank is connected to the hot gas inlet end of the cooler, and the nitrogen source is connected with the upper part of the storage tank. According to the device disclosed by the utility model, the purging medium is selected from slaked lime particles or rice and is added into the cooler along with high-temperature process gas or flue gas, and the purging medium particles impact the pipe wall of the cooler at a high speed along with hot gas, so that the effect of stripping and removing attachments on the pipe wall is achieved, and the heat exchange efficiency of the cooler is maintained; and long-period production and stable operation of the device are ensured.

Description

Technical Field

[0001] The utility model belongs to the technical field of methanol to olefins (MTO), and relates to a sootblowing device for maintaining cooler efficiency. Background Art

[0002] The reactor in an MTO unit is a key element in the methanol-to-olefins (MTO) process. The internal temperature reaches approximately 450°C. The product gas produced after the reaction carries a small amount of catalyst. After cooling, it is piped to downstream processes for product separation and refining. The regenerator, which chars and regenerates the solid catalyst in the reactor, operates at approximately 650°C. The charred, high-temperature flue gas, carrying a small amount of catalyst, is cooled and discharged into the atmosphere through a pipe.

[0003] The coolers at the reactor and regenerator outlets of an MTO unit are used to cool high-temperature process and flue gases before delivery to downstream processes. The gases from the reactor and regenerator outlets carry trace amounts of solid particles—catalyst fines. When the high-temperature gases enter the coolers for cooling, these fines adhere to the cooler tube walls. As the amount of fines on the tube walls increases, the cooler's heat exchange efficiency decreases, causing the cooler outlet temperature to slowly rise and steam generation from the drum to decrease. This increased gas temperature also impacts the normal operation of downstream processes and equipment, leading to production fluctuations and certain economic losses.

[0004] There are other similar coolers in MTO catalytic cracking units and petrochemical plants, which are used to cool gases carrying catalysts or other solid particles. They also have the problem of reduced efficiency due to attachments on the cooler tube walls. Summary of the Invention

[0005] The purpose of the utility model is to provide a soot blowing device for maintaining the efficiency of the cooler, to solve the problem of the efficiency reduction of the gas cooler carrying catalyst or other solid particles due to the attachments on the tube wall, to achieve the purpose of peeling off and removing the solid catalyst fine powder attached to the cooler tube wall, to restore the heat exchange efficiency of the cooler, and at the same time ensure the safe production operation of the device.

[0006] In order to achieve the above-mentioned purpose of the invention, the present invention adopts the following technical solutions:

[0007] A sootblowing device for maintaining cooler efficiency comprises a cooler and a steam drum for cooling hot gas containing solid particles. The device is characterized in that it also comprises a storage tank and a nitrogen source. The storage tank is filled with a purge medium and its bottom is connected to the hot gas inlet of the cooler. The nitrogen source is connected to the upper part of the storage tank.

[0008] Furthermore, the purge medium is selected from slaked lime particles, rice, or other inorganic solid substances that are inert to materials and equipment.

[0009] The purge medium used in the present invention is preferably slaked lime particles or rice, both of which will not affect the production operation of the device or product quality. Slaked lime particles are suitable for working conditions where hot gases such as high-temperature process gas contain water. When added to the front of the cooler, they absorb water and pulverize into smaller particles. They then collide with the pipe wall at high speed with the process gas, stripping away the catalyst fines. Rice is suitable for working conditions where high-temperature flue gas does not contain water. When added to the front of the cooler, it instantly expands into larger and softer particles when exposed to high temperatures. These particles collide with the pipe wall at high speed with the flue gas, stripping away the catalyst fines without damaging the pipe bundle.

[0010] Furthermore, a charging funnel is provided above the storage tank for adding the purge medium into the storage tank.

[0011] Furthermore, the nitrogen source is connected to the pipeline of the storage tank, and a nitrogen valve, a one-way valve and a pressure gauge are provided.

[0012] Furthermore, the steam drum is above the cooler, the circulating water outlet at the bottom of the steam drum is connected to the refrigerant inlet of the cooler, and the refrigerant outlet of the cooler is connected to the circulating water inlet at the top of the steam drum.

[0013] Furthermore, the cooler is a shell and tube heat exchanger, the hot gas flows through the tube side, and the drum circulating water flows through the shell side.

[0014] Beneficial Effects: This new sootblowing device maintains cooler efficiency by introducing a suitable purge medium into the cooler along with high-temperature process gas or flue gas. The purge medium particles follow the hot gas and impact the cooler tube walls at high speed, effectively stripping away any deposits on the tube walls. During production operations, if cooler efficiency decreases, timely treatment can be implemented to restore the cooler's heat exchange efficiency, ensuring long-term stable operation of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] FIG1 is a schematic structural diagram of a sootblowing device for maintaining cooler efficiency according to the present invention;

[0016] Among them, 1 is steam drum, 2 is cooler, 3 is charging funnel, 4 is storage tank, 5 is front feeding valve, 6 is rear feeding valve, 7 is nitrogen valve, 8 is check valve, and 9 is pressure gauge. DETAILED DESCRIPTION

[0017] The technical solutions of the present invention are further described in detail below through specific embodiments. However, it is necessary to point out that the following embodiments are only used to describe the content of the invention and do not constitute a limitation on the protection scope of the present invention.

[0018] like Figure 1As shown, the sootblowing device for maintaining the efficiency of the cooler of the present invention includes a cooler 2 and a steam drum 1, as well as a charging funnel 3, a storage tank 4, a nitrogen source, a front feed valve 5, a rear feed valve 6, a nitrogen valve 7, a one-way valve 8, and a pressure gauge 9. The cooler 2 is a shell and tube heat exchanger used for cooling high-temperature process gas and high-temperature flue gas containing solid particulate matter. The hot gas flows through the tube side, and the steam drum circulating water flows through the shell side. The bottom of the storage tank 4 is connected to one end of the hot gas inlet of the cooler 2 tube side, and the upper pipeline is connected to the nitrogen source. A nitrogen valve 7, a one-way valve 8, and a pressure gauge 9 are provided on the connecting pipeline. The purge medium is added to the storage tank 4 from the charging funnel 3 above the storage tank 4. The front feed valve 5 and the rear feed valve 6 are provided upstream and downstream of the storage tank 4, respectively.

[0019] The purge medium used is either slaked lime granules or rice, neither of which will affect the plant's operation or product quality. Slaked lime granules are suitable for use in conditions where the process gas contains water. When added to the front of cooler 2, they absorb water and pulverize into smaller particles. These particles then impact the pipe walls at high speed with the process gas, stripping away the fine catalyst powder. Rice is suitable for use in high-temperature, water-free flue gas. When added to the front of cooler 2, the high temperature instantly expands into larger, softer particles. These particles then impact the pipe walls at high speed with the flue gas, stripping away the fine catalyst powder without damaging the tube bundle.

[0020] When the device is in normal production operation, the high-temperature process gas or high-temperature flue gas enters the cooler 2 for cooling, and the heat taken out heats the boiler water in the drum 1 to generate steam (such as Figure 1 As shown), the high-temperature process gas or high-temperature flue gas contains solid catalyst particles, and the solid catalyst fine powder continues to adhere to the tube wall of the cooler 2, its heat exchange efficiency decreases, the outlet temperature of the cooler 2 continues to rise, and the steam production of the steam drum 1 slowly decreases. When the outlet temperature of the cooler 2 reaches the expected requirement, the cooler 2 needs to be soot-blown through the device to restore its heat exchange efficiency.

[0021] The specific operations are as follows:

[0022] First, put a certain amount of slaked lime particles or rice into the charging funnel 3, open the front feeding valve 5, close the rear feeding valve 6 and the nitrogen valve 7, and load the slaked lime particles or rice into the storage tank 4. Then close the front feeding valve 5, open the nitrogen valve 7, and pressurize the storage tank 4. By observing the pressure gauge 9, when the pressure is consistent with the nitrogen pipe network pressure, open the rear feeding valve 6, and the slaked lime particles or rice in the storage tank 4 are transported to the front of the cooler 2. When the pressure of the pressure gauge 9 drops to the same as the pressure of the cooler 2, it means that all the slaked lime particles or rice in the storage tank 4 have been added. The control room personnel judge whether multiple purges are needed by observing the changes in the outlet temperature of the cooler 2 and the steam production of the steam drum 1, and finally restore the original heat exchange efficiency of the cooler 2.

Claims

1. A sootblowing device for maintaining cooler efficiency, comprising a cooler (2) for cooling hot gas containing solid particles and a steam drum (1), characterized in that: It also includes a storage tank (4) and a nitrogen source. The storage tank (4) is filled with a purge medium, and its bottom is connected to the hot gas inlet end of the cooler (2). The nitrogen source is connected to the upper part of the storage tank (4).

2. The sootblowing device for maintaining cooler efficiency according to claim 1, characterized in that: The purging medium is selected from slaked lime particles or rice.

3. The sootblowing device for maintaining cooler efficiency according to claim 1, characterized in that: A charging funnel (3) is provided above the storage tank (4) for adding a purge medium into the storage tank (4).

4. The sootblowing device for maintaining cooler efficiency according to claim 1, characterized in that: The nitrogen source is connected to a pipeline of the storage tank (4), and a nitrogen valve (7), a one-way valve (8) and a pressure gauge (9) are provided.

5. The sootblowing device for maintaining cooler efficiency according to claim 1, characterized in that: The steam drum (1) is above the cooler (2), the circulating water outlet at the bottom of the steam drum (1) is connected to the refrigerant inlet of the cooler (2), and the refrigerant outlet of the cooler (2) is connected to the circulating water inlet at the top of the steam drum (1).

6. The sootblowing device for maintaining cooler efficiency according to claim 1, characterized in that: The cooler (2) is a shell and tube heat exchanger, with hot gas flowing through the tube side and circulating water from the drum (1) flowing through the shell side.

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